US4283948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cryogenic air sampler
Assignee: Sumitomo SHI Cryogenics of America Inc
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Filing: 1979-12-21
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Granted: 1981-08-18
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Expires: 1999-12-21
Abstract
Abstract Environmental gases, e.g. air are collected in an apparatus wherein a sample bottle containing a metering orifice for admitting the gas is contained within and cooled by a bath of liquid cryogen thus creating a partial vacuum inside the bottle to draw gas into the bottle where it is condensed and stored. The apparatus includes a source of cryogenic refrigeration disposed in an evacuated space above the liquid cryogen to condense liquid cryogen boil-off. By combining evacuation and cryogenic refrigeration the sample bottle holder can be rapidly cooled to operating temperature.
Inventors
- 👤 Ralph C. Longsworth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:32
CPC Classifications
G; G01; G01N; G01N1/00; G01N1/02; G01N1/22; G01N1/24; G01N2001/242; G01N2001/244
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
An apparatus for collecting and storing a sample of environmental gas comprising in combination: means to removably confine a sample bottle, said bottle having a metering orifice through which environmental gas can enter, in a bath of liquid cryogen said means including an evacuable space above said sample bottle allowing for liquid cryogen to boil-off and be confined therein; means to condense said cryogen boil-off thus maintaining said sample bottle at a temperature of just below the normal boiling temperature of said liquid cryogen; and means to effect rapid cool-down of said sample bottle.
Claim 2
Independent Claim
94 words
An apparatus for collecting and storing a sample of environmental gas comprising in combination: means to removably confine a sample bottle, said bottle having a metering orifice through which environmental gas can enter, in a bath of liquid cryogen said means including an evacuable space above said sample bottle allowing for liquid cryogen to boil-off and be confined therein; means to condense said cryogen boil-off thus maintaining said sample bottle at a temperature of just below the normal boiling temperature of said liquid cryogen; and means to effect rapid cool-down of said sample bottle.
Claim 3
Dependent Claim
29 words
An apparatus according to claim 1 wherein said means to removably confine said sample bottle includes a support plate to sealingly engage a complimentary surface on a vacuum dewar.
Claim 4
Dependent Claim
28 words
An apparatus according to claim 1 wherein said means to condense said cryogen boil-off includes a cryogenic refrigerator removably disposed within said evacuable space above said liquid cryogen.
Claim 5
Dependent Claim
41 words
An apparatus according to claim 1 wherein said refrigerator includes a heater disposed around its cold end said heater operated by a pressure controller connected to said evacuable space to prevent cryogen freeze out on said cold end of said refrigerator.
Claim 6
Dependent Claim
24 words
An apparatus according to claim 1 wherein said means to effect rapid cool-down of said sample bottle includes means to evacuate said evacuable space.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-17 | 1985-02-16 | 1985-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-17 | 1989-02-16 | 1989-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-17 | 1993-02-16 | 1993-08-18 | $7700.00 | Window Closed / Lapsed |